Jonathan was born 1750 and married Catherine December 12, 1791 in St. George's, Hanover Square, London. She was the daughter of George and Elizabeth Welden and was born in 1765 in Willesden, MDX. England. She was living in 1816 in Little Ealing, MDX. She was buried on June 27, 1816, at St. Mary's, Ealing, MDX. England.

National Archives (UK)
November 16, 1778
ACC/0276/164
Copy of court roll: manor of Ealing. Admission of Jonathan Knevett as heir of father, Jonathan Knevett.
Premises: messuage on piece of former waste land in Boston Lane.